Edge-mill.



No. 861,985. PATENTED JULY 30, 1907. H. HORN.

EDGE MILL.

APPLICATION FILED MAY 22, 1906.

f [3 :,a6 r

Z f K- L Z 1 g H F n 3Q .5" WITNESSES- \NVENTO-R, j HBNRxcH HQRN, Z BY j y Akin-e13.

HEINRICH HORN, OF GCRLITZ, GERMANY.

EDGE-MILL.

Specification of Letters Patent:

Patented July 30, 1907.

Application filed Ma" 22,1906. Serial No. 318,2 l4.

To all whom it may concern:

Be it known that I, HEINRICH HORN, a subject of the Prince of Reuss, junior line, residing at 12 Biesnitzerstrasse, Gorlitz, Silesia, in the Kingdom of Prussia and Empire of Germany, have invented new and useful Improvements in Edge-Mills, of which the following is a specificationl My invention relates to edge mills.

Use has already been made of edge mills, upon the grinding surface of which the material is displaced towards the center and again to the outside in order to be reduced step by step. In these edge mills the grinding surface is however partly or wholly interrupted, so that the material, as it passes over the apertures in the grinding surface, is liable to leave the edge mill insul'liciently reduced or pulverized. Edge mills having a full or continuous grinding surface are also well known, which cause the material to roll round a certain number of times and then to be removed without distinctionfrom the grinding surface. In this case all the hard parts, such as pieces of iron, and insufficiently reduced material can leave the mill. This drawback is especially apparent when too much material is conducted to the mill, because a larger quantity of material is not rolled round oftener or longer than a smaller quantity admitted in the same time. The drawbacks of the before-mentioned two structures are obviated in the edge mill constructed according to my said invention the material being reduced by steps to a definite size of the grains upon an interrupted or continuous grinding surface.

In the accompanying drawing 1 have represented, by way of example, a constructional form of my said invention.

Figure 1 is a front elevation of the edge mill, in which the rim or flange of the grinding surface is partly removed. Fig. 2 is a vertical transverse section. Fig. 3 is a plan of the mill without the driving device for the runners.

The circular grinding surface I) is provided in the stationary pan is which has at its periphery a'high rim or flange o, and at its center, surrounded by an annular aperture 0, a step bearing 1) for the runner shaft q, the upper end of which is fitted to turn in a bearing p secured to transverse supports p p upon columns 11*, p', p, p on the rim or flange of the grinding surface. At the upper end of the shaft is a bevel wheelg gearing with a small bevel wheel q on a horizontal shaft g held in bearings (1 upon the transverse supports p p and carrying at its other end a fixed pulley (1 and a loose pulley g Upon the shaft (1 is fixed a support 1' provided with two bearings r and r having bores which cross the shaft at right angles and receive the shafts 'n, n of cranks m, m, upon the journals Z, l of which the runners a and i are adapted to turn. The support 1 carries moreover the scraper holders 8, 3 having sockets u, a a a 10 provided with prismatic bores for the reception of the prismatic rods t, t t, t and L of the scrapers d, e, f, g and h. For the rod 25 of the scraper 1" there is a special socket to also furnished with a prismatic bore corresponding to the section of the rod t.

I The rods t, t, t t t, L are secured in the sockets u,

a, a a a", n by means of set screws 1). The shaft -(1 with the runners a, i and the scrapers d, e, f, f, g, h

is turned in the direction indicated by the arrow in Fig. 3, while the grinding surface b is stationary.

In the constructional form shown the material to be ground is admitted from the outside and leaves the edge mill through the aperture 0 at the center of the pan It. The scrapers d, c, f and f move in close contact with the grinding surface 1), while the scraper g is at a distance of say of an inch, and the scraper h at a distance of say of an inch above the grinding surface. The material thrown over or from the flange or rimo or otherwise fed upon the pan 70 from the outside is first pushed by the scraper 'd upon the outer half of the grinding surface I), then the runner a, the scraper g and the runner 1' pass over the same. Next the scraper c pushes the material upon the inner half of the grinding surface b, and the runner a, the scraper h and the runner '5 pass over the same. Finally the material is pushed by the scraper f towards the center and falls through the aperture c from the mill. Such parts of the material as have not yet been reduced to a size corresponding for instance to of an inch are again pushed outward by the scraper g, and are then conducted once more under the runner a by the scraper d, This operation is repeated until all the parts of the material are reduced in size to grains of i of an inch and then pass under the scraper g. In like manner the scraper h pushes all insufficiently reduced parts of the material to the outside, in order to conduct them under the runners "i, a until they have been reduced to the desired size of the grains, such as g of an inch.

According to the desired fineness of the ground material the scrapers g, h are adjusted in height. Only properly reduced material is conducted by the scrapers g, h to the second runner 1'. Thus the second runneri accomplishes the finishing work, and the first runner a the roughing work. 7

The outlet aperture 0 is almost completely surrounded by the scrapers f, f, g and h, and the scrapers g, h

are arranged so as to join each other. Bythis means I the material introduced at any point is prevented from passing to the outside again through the aperture 0 without having been subjected to all the steps of the reduction in the proper order. The material may also be ground in three or more steps, instead of two, by each runner, if a correspondingly greater number of scrapers is provided in a suitable manner.

It will be understood that my said invention is not not being raised,

What 1 claim as my invention, and desire to secure by Letters Patent is i 1. In an'edge mill, the combination of a pan having a central outlet opening, and a continuous grinding surface provided in the pan, with two runners, scrapers arranged in front of one runner and adapted to pass in close contact with the grinding surface and to displace the material towards the center and other scrapers arranged in front of the second runner at such a distance from the grinding surface as to conduct the insufliciently pulverized material to the outer periphery of the grinding surface and allow' the sufficiently pulverized material to pass under the second runner.

2. In an edge mill, the combination of a pan having a central outlet opening, and a continuous grinding surface provided in the pan, with two runners, scrapers arranged in front of one runner and adapted to pass in close contact, with the grinding surface and to displace the material towards the center, other scrapers arranged in front of the second runner at such a distance from the grinding surface as to conduct the insuiliciently pulverized material to the outer periphery of the grinding surface and allow the sufficiently pulverized material to pass under the second runner and means for adjusting the distance of the second scrapers from the grinding surface.

3. In an edge mill, thecombination of a pan having a central outlet opening, and a continuous grinding surface provided in the pan, with two runners, scrapers arranged in front of one runner and adapted to pass in close contact with the grinding surface and to displace the material towards the center, other scrapers arranged in front of the second runner at such a distance from the grinding surface as to conduct the insulficiently pulverized material to the outer periphery of the grinding surface and allow the sulficiently pulverized material to pass under the second runner, and thence to the scraper which conducts it to the discharge opening.

4. In an edge mill, the combination of a pan having a central outlet opening and a continuous grinding surface provided in the pan, with two runners, scrapers arranged in front of one runner and adapted to pass in close contact with the grinding surface and to displace the material towards the center, other scrapers arranged in front of the second runner at such a distance from the grinding surface as to conduct the insuiiiciently pulverized material to the outer periphery of the grinding surface and allow the sufficiently pulverized material to pass under the second run ner and thence to the scraper which conducts it to the discharge opening, the last named scraper and the innermost scrapers of the aforesaid scrapers being so arranged as to completely surround the discharge opening.

In testimony whereof I have signed my name to this specification in the presence of two subscribing witnesses.

HEINRICH HORN. Witnesses:

HERBERT SMITH, PAUL GKUNDY. 

